Ink-jet recording is a printing method in which an ink is ejected as small droplets from a fine nozzle to record characters or images on the surface of a recording material. The ink-jet recording techniques which have been put to practical use include: a technique in which electrical signals are converted to mechanical signals by means of an electrostrictive element to intermittently eject the ink residing in the nozzle head and thereby record characters or symbols on the surface of a recording material; and a technique in which the ink residing in the nozzle head is bubbled by rapidly heating that part of the ink which is located very close to the orifice to intermittently eject the ink by means of the volume increase due to the bubbles and thereby record characters or symbols on the surface of a recording material.
The ink which is ejected from the nozzle head in those techniques generally is one fed from an ink cartridge mounted on the ink-jet recording apparatus (printer). The ink cartridge housing contains an ink holding member, which is impregnated with the ink. The ink thus stored in the cartridge is discharged as the printer is used. Herein, particulate substances which are physically peeled off from the ink holding member are foreign matter for the ink and are causative of defects. Such defects include 1) the ink is not delivered in a desired amount and 2) printing is disturbed. To solve the defects, it is known an ink cartridge having a metal mesh disposed as a filter in the ink passage so as to capture foreign matter which has come into the ink-jet recording ink.
However, the use of a metal mesh has had a problem that it increases the production cost of an ink cartridge because the metal mesh has a high material cost and because it is necessary to fusion-bond the edge of the metal mesh to the inner wall of the ink passage in order to surely attach the metal mesh to the ink passage.
There has been another problem. Most of the members constituting an ink cartridge are usually made of a resin such as polypropylene. However, upon recycling such resin products, it is necessary to remove the metal mesh filter from the ink cartridge. Thus, ink cartridges employing a metal mesh filter have poor suitability for recycling.